Fletcher, Mary A, Rosenthal, Martin, Antoni, Michael et al. · Behavioral and brain functions : BBF · 2010 · DOI
This study measured a stress-related substance called neuropeptide Y (NPY) in the blood of ME/CFS patients and compared it to healthy people and people with Gulf War Illness. The researchers found that ME/CFS patients had significantly higher NPY levels, and these levels correlated with how severe their symptoms were—including stress, depression, fatigue, and cognitive problems. This suggests NPY could be a useful blood test to help identify ME/CFS and track symptom severity.
Finding a biological marker for ME/CFS symptom severity could improve diagnosis and treatment monitoring, particularly since the condition is currently diagnosed by clinical criteria alone. This work provides evidence that stress-response system dysregulation is measurable in ME/CFS and offers a potential objective tool to stratify patients and evaluate treatment response.
This study does not establish whether elevated NPY causes ME/CFS symptoms or is merely a consequence of the illness—correlation does not imply causation. It also does not prove NPY is specific to ME/CFS, since only one fatigue comparison group (GWI) was included. The cross-sectional design cannot determine whether NPY changes precede symptom onset or follow from chronic illness.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Fletcher, Mary A, Rosenthal, Martin, Antoni, Michael, Ironson, Gail, Zeng, Xiao R, Barnes, Zachary, et al. (2010). Plasma neuropeptide Y: a biomarker for symptom severity in chronic fatigue syndrome.. Behavioral and brain functions : BBF. https://doi.org/10.1186/1744-9081-6-76
BibTeX
@article{mecfsatlas-fletcher-2010-plasma-neuropeptide,
author = {Fletcher, Mary A and Rosenthal, Martin and Antoni, Michael and Ironson, Gail and Zeng, Xiao R and Barnes, Zachary and Harvey, Jeanna M and Hurwitz, Barry and Levis, Silvina and Broderick, Gordon and Klimas, Nancy G},
title = {Plasma neuropeptide Y: a biomarker for symptom severity in chronic fatigue syndrome.},
journal = {Behavioral and brain functions : BBF},
year = {2010},
doi = {10.1186/1744-9081-6-76},
note = {PubMed: 21190576},
url = {https://www.mecfsatlas.com/evidence/fletcher-2010-plasma-neuropeptide},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-30. https://www.mecfsatlas.com/evidence/fletcher-2010-plasma-neuropeptide
Contribute
Private, reviewed by a human. Not a public comment thread.